A indexable tool having cutting inserts respectively attached to a plurality of insert pockets located along a rotation direction of an outer peripheral surface at the front end of a holder has conventionally been used as a cutting insert (rotating tool), such as a face milling cutter or an end mill. As the cutting inserts, those intended to decrease cutting resistance by disposing grooves for dividing a cutting edge into divided cutting edges on a side surface have been used (for example, refer to Japanese Unexamined Patent Publication No. 9-57519). Cutting processing with these cutting inserts generates a plurality of chips finely divided in the width direction thereof.
However, the foregoing conventional cutting inserts have suffered from the problem that the finely divided chips cannot smoothly be discharged. For example, a discharge direction of the chips generated by the divided cutting edges becomes unstable, and the chips may be caught in the grooves, thereby damaging the cutting inserts, the holder, or a machined surface. This problem is significant when a workpiece is a material having rich ductility.